Inegalitate conditionata 3

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Marius Mainea
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Inegalitate conditionata 3

Post by Marius Mainea »

Fie a,b,c nenegative cu a+b+c=1. Demonstrati ca:

\( \frac{a^2b^2}{1-ab}+\frac{b^2c^2}{1-bc}+\frac{c^2a^2}{1-ca}\le \frac{1}{12}. \)
Marius Mainea
Gauss
Posts: 1077
Joined: Mon May 26, 2008 2:12 pm
Location: Gaesti (Dambovita)

Post by Marius Mainea »

Avem \( ab\le(\frac{a+b}{2})^2\le (\frac{a+b+c}{2})^2=\frac{1}{4} \) si analoagele deci


\( LHS\le\frac{4}{3}(a^2b^2+b^2c^2+c^2a^2)\le \frac{1}{12} \)(demonstrati)
Marius Mainea
Gauss
Posts: 1077
Joined: Mon May 26, 2008 2:12 pm
Location: Gaesti (Dambovita)

Post by Marius Mainea »

Marius Mainea wrote:
\( LHS\le\frac{4}{3}(a^2b^2+b^2c^2+c^2a^2)\le \frac{1}{12} \)(demonstrati)
Fie a= max(a,b,c)

\( ab+ac=a(b+c)\le (\frac{a+b+c}{2})^2=\frac{1}{4} \)
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